The Centers for Disease Control and Prevention (CDC) considers Chagas Disease as one of the five neglected parasitic infections (NPIs) that require public health action based on records of its severity and widespread infection.
A new study published on May 18 In the journal PLOS Neglected Tropical Diseases, however, claims that the disease may be more fatal than experts believe because cases of death caused by the Trypanosoma cruzi have been under-reported.
Researchers from University of Sao Paulo in Brazil studied more than 8,000 people who donated blood from 1996 to 2000 and found that among the participants, 2,842 donors tested positive for Chagas disease at the time of blood donation while 5,684 tested negative. The researchers studied the participants' records for the next 14 years and crossed reference their identities with death certificates recorded in the Brazil national mortality information system (SIM).
Among the Chagas-positive blood donors, 5.6 percent or 159 participants died during the 14-year time frame, while only 1.8 percent or 103 Chagas-negative participants passed away.
In the more chronic stages of Chagas disease, patients can develop cardiac abnormalities and intestinal complications but only 58 percent of cardiac deaths were recorded as Chagas-related.
When the researchers added abnormal cardiac-related deaths to the equation — one of the disease's more fatal symptoms — the result showed that Chagas-positive participants have a 17.9 times higher risk of heart disease leading to death.
"The fact that Chagas disease was not reported as an underlying or associated cause of death on the death certificate of 42% of seropositive donors that died due to cardiac causes demonstrates under ascertainment of Chagas disease pathogenesis, highlighting its status as a neglected tropical disease," the researchers write.
The Kissing Bug Of Death
Triatomine bugs, more commonly known as the kissing bug due to its preference for biting sleeping humans close to the lips and eyes, transfer the T. Cruzi parasite through its feces, which it leaves near or in the broken skin after feeding.
The parasite then enters the bloodstream to slowly wreak havoc in the human body, but its symptoms are mostly mild and, in some cases, patients don't even experience any.
Despite its asymptomatic nature, however, the researchers concluded that T. cruzi continues to affect an infected person's body and can result in death.
"What the parasite does to the body takes a long time; (it) slowly goes into the heart and destroys it," Dr. Ester Cerdeira Sabino explained. Dr. Sabino is a co-leader in the study.
Researchers continue to find a way to develop an effective drug to kill the T. cruzi parasite but there is currently no vaccine against the Chagas disease. So far, the only solution is to control the kissing bug population in order to stop the spread of the parasite.